Effects of Single and Combined Drought and Salinity Stress on the Root Morphological Characteristics and Root Hydraulic Conductivity of Different Winter Wheat Varieties

Yuanyuan Fu; Penghui Li; Abdoul Kader Mounkaila Hamani; Sumei Wan; Yang Gao; Xingpeng Wang

doi:10.3390/plants12142694

Effects of Single and Combined Drought and Salinity Stress on the Root Morphological Characteristics and Root Hydraulic Conductivity of Different Winter Wheat Varieties

Plants (Basel). 2023 Jul 19;12(14):2694. doi: 10.3390/plants12142694.

Authors

Yuanyuan Fu^{1

2}, Penghui Li¹, Abdoul Kader Mounkaila Hamani¹, Sumei Wan², Yang Gao¹, Xingpeng Wang³

Affiliations

¹ Institute of Farmland Irrigation, Chinese Academy of Agricultural Sciences, Xinxiang 453002, China.
² College of Agronomy, Tarim University, Alar 843300, China.
³ College of Water Conservancy and Architecture Engineering, Tarim University, Alar 843300, China.

Abstract

Water shortages and crop responses to drought and salt stress are related to the efficient use of water resources and are closely related to food security. In addition, PEG or NaCl stress alone affect the root hydraulic conductivity (Lpr). However, the effects of combined PEG and NaCl stress on Lpr and the differences among wheat varieties are unknown. We investigated the effects of combined PEG and NaCl stress on the root parameters, nitrogen (N) and carbon content, antioxidant enzymes, osmotic adjustment, changes in sodium and potassium, and root hydraulic conductivity of Yannong 1212, Heng 4399, and Xinmai 19. PEG and NaCl stress appreciably decreased the root length (RL), root surface area (RS), root volume (RV), K⁺ and N content in shoots and roots, and Lpr of the three wheat varieties, while the antioxidant enzyme activity, malondialdehyde (MDA), osmotic adjustment, nonstructural carbon and Na⁺ content in shoots and roots, etc., remarkably remained increased. Furthermore, the root hydraulic conductivity had the greatest positive association with traits such as RL, RS, and N and K⁺ content in the shoots of the three wheat varieties. Moreover, the RL/RS directly and actively determined the Lpr, and it had an extremely positive effect on the N content in the shoots of wheat seedlings. Collectively, most of the root characteristics in the wheat seedlings decreased under stress conditions, resulting in a reduction in Lpr. As a result, the ability to transport nutrients-especially N-from the roots to the shoots was affected. Therefore, our study provides a novel insight into the physiological mechanisms of Lpr.

Keywords: PEG stress; combined PEG and NaCl stress; protective enzyme activities; root hydraulic conductivity; salt stress.

Grants and funding

This research was funded by the National Natural Science Foundation of China (National Natural Science Fund Committee of China, 51879267), the China Agriculture Research System of MOF and MARA (Chinese Academy of Agricultural Sciences, CARS-03-19), the Agricultural Science and Technology Innovation Program (Ministry of Agriculture and Rural Affairs of the People’s Republic of China, ASTIP), and the Central Public-Interest Scientific Institution Basal Research Fund (Farmland Irrigation Research Institute, CAAS, FIRI2022-17).